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A fuse operates due to which effect of the electric current?
Magnetic
Electrostatic
Heating
Chemical
Heating
An electric fuse operates based on the thermal effect of electric current, specifically Joule heating. When current exceeds a safe limit, the heat generated by the fuse element causes it to melt and break the circuit, protecting equipment from overcurrent damage.
An electric fuse operates based on the thermal effect of electric current, specifically Joule heating. When current exceeds a safe limit, the heat generated by the fuse element causes it to melt and break the circuit, protecting equipment from overcurrent damage.
H=I2Rt тАФ Joule's Law of heating where H is energy in Joules, I is current in Amperes, R is resistance in Ohms, and t is time in seconds.
The principle is governed by Joule's Law of heating, which states that heat produced is directly proportional to the square of the current, the resistance of the wire, and the time for which current flows. As the current increases beyond the rated value, the rate of heat generation H=I2Rt increases rapidly. Once the melting temperature of the fuse material (usually low-melting-point alloys like lead-tin) is reached, the element melts, creating an open circuit that stops the flow of current.
Fuses are connected in series with the live conductor.
The fuse material must have a low melting point and high resistivity.
The operation is independent of voltage polarity.
The fuse acts as a sacrificial device to protect sensitive components.
Cost-effective and simple design
Provides reliable protection against short circuits
No maintenance required during normal operation
Requires manual replacement after operation
Cannot distinguish between minor overloads and severe faults as precisely as a circuit breaker
Risk of deterioration due to aging of the element
Domestic wiring circuits
Automotive electrical systems
Electronic power supplies
Magnetic effect is the basis for Circuit Breakers and Relays.
Chemical effect is primarily associated with electrolysis and battery charging.
Electrostatic effect relates to potential differences and capacitance, not common for current-based protection.
C is correct тАФ An electric fuse utilizes the heating effect of current to disconnect a circuit when the flow exceeds the rated threshold.
Always remember that fuses protect against overcurrent via thermal effects, whereas magnetic circuit breakers often employ electromagnetic relay principles for faster fault interruption.